固相萃取-高效液相色谱法测定有机肥中四环素类抗生素药物残留

摘要

建立了固相萃取-高效液相色谱(SPE-HPLC)法测定有机肥中土霉素(OTC)、四环素(TC)和金霉素(CTC)3种四环素类抗生素残留的方法.肥料样品采用甲醇、EDTA和Mcllvaine缓冲液的混合液(pH=7.2)为提取液,用强阴离子交换柱(SAX)-亲水亲脂萃取柱(HLB)串联进行纯化和富集.采用甲醇-乙腈-0.01mol/L草酸溶液为流动相,进行HPLC分析.3种抗生素的线性范围为0.10～20mg/L,OTC、TC和CTC的检测限分别为0.03、0.03和0.05 mg/L.不同添加水平的样品加标回收率为64%～86%,RSD在4.14%～8.16%之间.该方法测定了上海市场上40种肥料,发现部分样品有四环素类抗生素的残留物.%A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography (HPLC) has been developed for simultaneous determination of three kinds of tetracycline antibiotic ( oxytetracycline, OTC, tetracycline, TC and chlortetracycline, CTC) residues in organic manure.The samples were extracted with a mixture of methanol, EDTA and Mcllvaine buffer at pH = 7.2.The extracts were then cleaned-up and enriched by a tandem SPE method using an Isolute SAX anion exchange cartridge and an Oasis HLB pelymerie cartridge.Analysis was performanced by HPLC and the mobile phase was methanol-acetonitrile -0.01 mol/L oxalic acid solution.The calibration curve was linear in the range 0.1 ～ 20 mg/L.The limit of detection (LOD) was 0.03 mg/L, 0.03 mg/L, 0.05 mg/L and the recovery rates were 64％ ～ 86％ with RSD ranging from 4.14％ to 8.16％ for OTC, TC, CTC in organic manure.With the method, 40 kinds of manures from Shanghai market were detected and the results showed that some samples contained tetracycline antibiotic residues.